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                                                                   Exhibit 10(i)

                            CONTRIBUTION AGREEMENT


     THIS CONTRIBUTION AGREEMENT is made and entered into this 3rd day of
November, 1997, by and among (i) HMCE ASSOCIATES LIMITED PARTNERSHIP, R.L.L.P.
("HMCE"), a Virginia limited liability limited partnership, (ii) HB LIMITED
PARTNERSHIP, R.L.L.P. ("HB"), a Virginia limited liability limited partnership,
and (iii) IFA NUTLEY PARTNERS, LLC, a Delaware limited liability company
("IFA").

                                   RECITALS

     A.   HMCE owns a leasehold estate in certain land in Fairfax County,
Virginia, and the building, improvements, fixtures and equipment thereon, which
has a street address of 9300 Lee Highway, Fairfax, Virginia.

     B.   HB owns a leasehold estate in certain land in Fairfax County,
Virginia, and the building, improvements, fixtures and equipment thereon, which
has a street address of 9302 Lee Highway, Vienna, Virginia.

     C.   HMCE, HB and IFA have agreed to form a limited liability company under
the laws of the State of Delaware, to be known as Hunters Branch Partners,
L.L.C. ("Hunters Branch LLC"), for the purpose of acquiring, owning and
operating the leasehold estates, buildings, improvements, fixtures and equipment
referred to in Recitals A and B.

     D.   HMCE and HB have agreed to transfer and convey to Hunters Branch LLC
the leasehold estates, buildings, improvements, fixtures, equipment and certain
other tangible and intangible assets and properties owned by each of them and
used by them in connection with the management, operation, maintenance and
repair of the buildings and improvements.

     E.   IFA has agreed to make certain capital contributions to Hunters Branch
LLC.

     F.   ICF Kaiser International, Inc. ("ICF Kaiser"), which is presently a
tenant in the buildings owned by HMCE and HB, has agreed to cancel and terminate
its existing leases, to cause one of its subsidiaries to enter into new leases
with Hunters Branch L.L.C. and to guaranty those new leases.

     NOW, THEREFORE, in consideration of the mutual promises hereinafter set
forth and of other good and valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the parties agree as follows:

                                   ARTICLE I

                                  Definitions

     Section 1.1    General Interpretive Principles.  For purposes of this
Agreement, except as otherwise expressly provided or unless the context
otherwise requires, (i) the terms defined in this Section have the meanings
assigned to them in this Section and include the plural as well as the singular,
and the use of any gender herein shall be deemed to include the other genders;
(ii) accounting terms not otherwise defined herein have the meanings assigned to
them in accordance with generally accepted accounting principles; (iii)
references herein to "Articles," "Sections," "subsections," "paragraphs" and
other subdivisions without reference to a document are to designated Articles,
Sections, subsections, paragraphs and other subdivisions of this Agreement; (iv)
a reference to a subsection without further reference to a Section is a
reference to such subsection as contained in the same Section in which the
reference appears, and this rule shall also apply to paragraphs and other
subdivisions; (v) a reference to an Exhibit or a Schedule without a further
reference to the document to which the Exhibit or Schedule is attached is a
reference to an Exhibit or Schedule to this Agreement; (vi) the words "herein,"
"hereof," "hereunder" and other words of similar import refer to this Agreement
as a whole and not to any particular provision; and (vii) the word "including"
means "including, but not limited to."

     Section 1.2    Defined Terms.  For all purposes of this Agreement, the
following terms shall have the respective meanings set forth below:

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               "9300 Building" shall mean the building, fixtures and other
improvements located on the 9300 Land.

               "9300 Ground Lease" shall mean the Ground Lease dated May 29,
1986, between Ground Lessor, as Landlord, and HMCE, as tenant, as recorded in
Deed Book 6398, at page 127, among the Land Records of Fairfax County, Virginia,
as amended by a First Amendment to Ground Lease dated August 18, 1987, recorded
in Deed Book 6847, at page 660, among said Land Records, a Second Amendment to
Ground Lease dated September 22, 1987, recorded in Deed Book 6859, at page 278,
among said Land Records, and a Third Amendment to Ground Lease dated June 23,
1988, recorded in Deed Book 7186, at page 1643, among said Land Records.

               "9300 Land" shall mean the parcel of land, containing 6.97700
acres, more or less, described in Exhibit A-1.

               "9300 ICF Space Lease" shall mean the Lease Agreement, dated
January 30, 1987, between HMCE, as landlord, and ICF Kaiser, as tenant, as
amended, pursuant to which ICF Kaiser leases all of the 9300 Building.

               "9300 New ICF Space Lease" shall mean the Lease Agreement, dated
as of the Closing Date, substantially in the form attached as Exhibit H,
pursuant to which ICF Leasing will lease all of the 9300 Building.

               "9300 Leasehold Estate" shall mean the leasehold estate in the
9300 Land and the 9300 Building created by the 9300 Ground Lease.

               "9302 Building" shall mean the building, fixtures and other
improvements located on the 9302 Land.

               "9302 Ground Lease" shall mean the Ground Lease dated November 3,
1987, between Ground Lessor, as Landlord, and HMCE, as tenant, as recorded in
Deed Book 6909, at page 793, among the Land Records of Fairfax County, Virginia,
as amended by a First Amendment to Ground Lease dated June 23, 1988, recorded in
Deed Book 7186, at page 1665, among said Land Records, and as assigned by HMCE
to HB pursuant to an Assignment and Assumption of Ground Lease dated April 1,
1990, recorded in Deed Book 7589, at page 682, among said Land Records.

               "9302 Land" shall mean the parcel of land, containing 6.92704
acres, more or less, described in Exhibit A-2.

               "9302 ICF Space Lease" shall mean the Lease Agreement, dated
April 27, 1988, between HMCE, as landlord, and American Capital and Research
Corporation, as tenant, as amended, pursuant to which ICF Kaiser leases a
portion of the 9302 Building.

               "9302 New ICF Space Lease" shall mean the Lease Agreement, dated
as of the Closing Date, substantially in the form attached as Exhibit I,
pursuant to which ICF Leasing will lease a portion of the 9302 Building.

               "9302 Leasehold Estate" shall mean the leasehold estate in the
9302 Land and the 9302 Building created by the 9302 Ground Lease.

               "Additional Rent" shall mean all reimbursements of Operating
Expenses, administrative charges, reimbursements of Real Estate Taxes,
retroactive rent escalations, insurance cost reimbursements, and all other
amounts and charges payable by Tenants to HMCE and HB, as landlords, under their
Space Leases (other than Minimum Rent), but shall not include Security Deposits.

                                      -2-
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               "Agreement" shall mean this Agreement in its present form or as
it may be amended, modified or supplemented from time to time.

               "Bill of Sale" shall mean a bill of sale substantially in the
form attached as Exhibit E.

               "Buildings" shall mean the 9300 Building and the 9302 Building.

               "Business Days" shall mean any day of the week other than
Saturday, Sunday or a day on which banking institutions in either New York, New
York, or Washington, D.C., are obligated or authorized by law to close.

               "Certificate of Formation" shall mean the Certificate of
Formation of Hunters Branch LLC substantially in the form attached as Exhibit B.

               "Closing" shall have the meaning set forth in Section 9.1.

               "Closing Date" shall mean the date on which the closing of the
Nomura Loan is consummated.

               "Code" shall mean the Internal Revenue Code of 1986, as amended.

               "Contracts" shall mean all written contracts and agreements
entered into by HMCE, HB or their management agent providing for the management,
operation, supply, maintenance, repair, advertising or promotion of the Real
Property, including service agreements, maintenance contracts, cleaning
contracts, employment contracts, contracts for the purchase or delivery of
labor, services, materials or supplies and equipment rental agreements or leases
of tangible personal property, but excluding insurance policies and any
currently existing property or asset management agreement(s).

               "Delinquent Rent" shall mean Rent which is due and payable by a
Space Tenant on or before the Proration Date but has not been paid by the
Proration Date.

               "Effective Date" shall mean the date of this Agreement.

               "Existing TIAA Mortgage Loans" shall mean the loans made by TIAA
to HMCE and HB which are secured by Mortgages on the Leasehold Estates and the
Land and which will have an unpaid principal balance, as of the Effective Date,
of $32,648,358.28 (in the case of the loan for the 9300 Building) and
$30,376,731.58 (in the case of the loan for the 9302 Building).

               "General Assignment" shall mean an Assignment of Licenses,
General Intangibles and Warranties substantially in the form attached as Exhibit
G.

               "Governmental Authorities" shall mean any board, bureau,
commission, department or body of any municipal, county, state or federal
governmental unit, or any subdivision thereof, having or acquiring jurisdiction
over the Real Property or the management, operation, use or improvement thereof.

               "Ground Leases" shall mean the 9300 Ground Lease and the 9302
Ground Lease.

               "Ground Lessor" shall mean First Union Bank of Virginia, N.A.,
successor by merger to First American Bank of Virginia, as Trustee for J.
Willard Marriott, Jr., Richard E. Marriott and Snell Construction Corporation
under that certain trust agreement dated December 31, 1979.

               "Ground Lease Assignment" shall mean an Assignment and Assumption
of Ground Leases substantially in the form attached as Exhibit D.

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               "Ground Lease Rent" shall mean the rent payable to the Ground
Lessor under the Ground Leases.

               "ICF Leasing" shall mean ICF Kaiser Hunters Branch Leasing, Inc.,
a Delaware corporation.

               "ICF Kaiser Lease Guaranty" shall mean a Guaranty of Lease in the
form attached to the 9300 New ICF Space Lease and the 9302 New ICF Space Lease.

               "LLC Agreement shall mean the Limited Liability Company Agreement
substantially in the form attached as Exhibit C.

               "Land" shall mean the 9300 Land and the 9302 Land.

               "Leasehold Estates" shall mean the 9300 Leasehold Estate and the
9302 Leasehold Estate.

               "Licenses" shall mean all licenses, authorizations, approvals and
permits issued by Governmental Authorities relating to HMCE's and HB's (and not
any Space Tenant's) use, operation, ownership or maintenance of the Real
Property.

               "Membership Interest" shall mean an interest as a Member in
Hunters Branch LLC.

               "Minimum Rent" shall mean all base rent, minimum rent or basic
rent (including cost-of-living adjustments) payable in fixed installments and
fixed amounts for stated periods by Space Tenants under their Space Leases.

               "Mortgage" shall mean a mortgage, deed of trust or other type of
security instrument of the type commonly given to secure loans or advances on,
or the unpaid purchase price of, real property in the jurisdiction in which such
real property is located.

               "Nomura" shall mean Nomura Asset Capital Corporation.

               "Nomura Commitment" is that certain commitment letter from Nomura
dated September 29, 1997 pursuant to which Nomura has agreed to make the Nomura
Loan.

               "Nomura Loan" shall mean that certain loan to be made by Nomura
in the approximate amount of $58,000,000.00, secured by Mortgages on the Real
Property and the Leasehold Estates, pursuant to the Nomura Commitment.

               "Operating Expenses" shall mean all costs, expenses, charges and
fees incurred by HMCE, HB or Hunters Branch LLC, as the case may be, relating to
the management, operation, maintenance and repair of the Real Property,
including Ground Lease Rent, electricity, gas, water and sewer charges,
telephone and other public utilities, common area maintenance charges, insurance
premiums, vault charges, personal property taxes, excise taxes on Rent, business
occupational taxes, periodic charges payable under Contracts, periodic fees
payable under transferable Licenses for the operation (as opposed to the
construction) of the Real Property which are assigned to Hunters Branch LLC,
salaries, wages, vacation and sick pay, pension, welfare and other fringe
benefits, employee-related taxes and other labor costs, but not including any
costs, expenses, charges or fees which are the direct responsibility of a Space
Tenant or any costs, expenses, charges or fees that are subject to cost-of-
living adjustments under a GSA Lease.

               "Option Agreement" shall mean the Option Agreement between
Hunters Branch LLC, Ground Lessor and IFA substantially in the form attached as
Exhibit J.

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               "Permitted Exceptions" shall mean (i) the lien of current Real
Estate Taxes not yet due and payable, (ii) the Space Leases and any additions,
renewals and replacements thereof, (iii) the state of facts which would be
disclosed by an accurate survey of the Real Property, and (iv) the additional
exceptions approved by Nomura.

               "Person" shall mean an individual, estate, trust, partnership,
corporation, Governmental Authority or other legal entity.

               "Personal Property" shall mean all furniture, furnishings,
fixtures, equipment, maintenance vehicles, tools and other tangible personal
property of every kind and description owned by HMCE and HB on, attached to or
used or useful in connection with the management, operation, maintenance and
repair of the Buildings, including HMCE's inventory of spare and replacement
parts and its inventory of consumable supplies.

               "Property" shall mean that property being contributed by HMCE
pursuant to Section 2.3 of this Agreement.

               "Proration Date" shall mean the Closing Date.

               "Real Estate Taxes" shall mean all taxes, assessments, vault
rentals, and other charges, if any, general, special or otherwise, including all
assessments for schools, public betterments and general or local improvements,
levied or assessed upon or with respect to the ownership of and/or all other
taxable interests in the Real Property imposed by any public or quasi-public
authority having jurisdiction.

               "Real Property" shall mean the Land and the Buildings.

               "Reimbursable Expenses" shall mean all or a portion of the
Operating Expenses under Space Leases that are not Real Estate Taxes, which are
taken into account under a Space Tenant's Space Lease in determining the amount
of Additional Rent payable by the Tenant.

               "Rent" shall mean, collectively, Minimum Rent and Additional
Rent.

               "Security Deposits" shall mean all security deposits, access card
or key deposits, cleaning fees and other deposits (including any interest
accrued thereon in accordance with the terms of the Space Leases) relating to
space within the Buildings paid by Space Tenants to HMCE, HB or their managing
agent.

               "Space Lease and Contract Assignment" shall mean an Assignment
and Assumption of Certain Leases, Tenancies and Written Agreements in the form
attached as Exhibit F, providing for the assignment and assumption of all Space
Leases and Contracts to Hunters Branch LLC.

               "Space Leases" shall mean all written leases (other than
subleases entered into by Tenants), including all amendments, extensions,
modifications and supplements thereto, pursuant to which any Person uses or
occupies any part of the Real Property, including the 9300 ICF Space Lease and
the 9302 ICF Space Lease.

               "Space Tenants" shall mean all Persons leasing or occupying space
within the Real Property pursuant to the Space Leases.

               "TIAA" shall mean Teachers Insurance and Annuity Association of
America.

               "Utility Deposits" shall mean all deposits made by HMCE and HB
with the Persons providing water, sewer, gas, electricity, telephone and other
public utilities to the Real Property.

               "Warranties" shall mean all assignable warranties or guaranties
presently in effect from contractors, suppliers or manufacturers of personal
property installed in or used in connection with the Real Property or any work
performed or improvements included as a part of the Real Property.

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                                  ARTICLE II

       Formation of Hunters Branch LLC and Contribution of the Property

               Section 2.1  Merger of HB into HMCE. On or before the Closing
Date, HB shall be merged into HMCE in a statutory merger pursuant to Section 50-
73.48:4 of the Code of Virginia (1950). HMCE shall be the surviving limited
partnership in the merger. As provided in Section 50-73:48:4 of the Code of
Virginia (1950), upon the filing of Articles of Merger with the Virginia State
Corporation Commission, title to all assets and property owned by HB shall be
vested in HMCE by operation of law and all debts, liabilities and obligations of
HB shall automatically become the debts, liabilities and obligations of HMCE.

               Section 2.2  Formation of Hunters Branch LLC.

               (a)  Filing of Certificate of Formation. Before the Closing Date,
HMCE shall cause the Certificate of Formation to be filed with the Secretary of
State of the State of Delaware and shall cause Hunters Branch LLC to be
qualified to do business as a foreign limited liability company in the
Commonwealth of Virginia.

               (b)  Signing of LLC Agreement. On the Closing Date, and subject
to the terms and conditions of this Agreement, HMCE and IFA shall form Hunters
Branch LLC by executing and delivering the LLC Agreement, which shall be dated
as of the Closing Date.

               Section 2.3  Property to be Contributed by HMCE. On the Closing
Date, and subject to the terms and conditions set forth in this Agreement, HMCE
(on its own behalf and as successor by merger to HB) agrees to convey, transfer
and assign the following property to Hunters Branch LLC, as a capital
contribution:

               (a)  all right, title and interest of HMCE in and to the
Leasehold Estates;

               (b)  the Personal Property;

               (c)  all right, title and interest of HMCE in and to the Space
Leases (including any right of HMCE in and to Security Deposits) and the
Contracts;

               (d)  all right, title and interest of HMCE, if any, in and to all
transferable Licenses;

               (e)  all right, title and interest of HMCE  in and to the
Warranties; and

               (f)  the additional property, including money, described in
clauses (ii) and (iii) of Section 4.2(a) of the LLC Agreement.

HMCE shall transfer and assign good and marketable title to the Leasehold
Estates and good title to the Personal Property free and clear all liens,
encumbrances, easements, covenants, conditions, leases and other matters
affecting title, except for the Permitted Exceptions.

     Section 2.4  Property to be Contributed by IFA. On the Closing Date, and
subject to the terms and conditions of this Agreement, IFA shall pay to Hunters
Branch LLC, as a capital contribution, the amounts required by Section 4.2(b) of
the LLC Agreement by wire transfer of immediately available funds to a bank
account designated by HMCE. If required to do so by TIAA, in connection with the
purchase and/or discharge of the Existing TIAA Mortgage Loans, IFA shall make a
part of the capital contribution by wire transfer of immediately available funds
to a bank account designated by TIAA, to be applied by TIAA as a principal
payment of the Existing TIAA Mortgage Loans.

     Section 2.5  No Other Obligations Contributed or Assumed. Except as
provided in Section 2.3 and Section 2.4, and in Section 5.6, no other assets or
property of HB or HMCE shall be contributed to, and no other

                                      -6-
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liabilities or obligations of HB or HMCE shall be assumed by, Hunters Branch
LLC. All other assets and liabilities of HMCE shall remain the assets and
liabilities of HB and/or HMCE, as applicable.

                                  ARTICLE III

                 Representations and Warranties of HMCE and HB

     HMCE and HB make the representations and warranties in this Article to ICF
Kaiser and IFA for the purpose of inducing them to execute and deliver this
Agreement and to consummate the transactions contemplated by this Agreement:

     Section 3.1  Organization.  Each of HMCE and HB  is a limited partnership
duly organized, validly existing and in good standing under the laws of the
Commonwealth of Virginia.

     Section 3.2  Authorization.  The requisite number of the general and
limited partners of HMCE and HB required by the Limited Partnership Agreements
pursuant to which they are organized has authorized the execution and delivery
of this Agreement and the transactions contemplated hereby, and the individuals
who are executing and delivering this Agreement on behalf of HMCE and HB have
been fully authorized and empowered to do so.

     Section 3.3  No Conflicting Agreements.  The execution and delivery by HMCE
and HB of, and the performance and compliance by them with the terms and
provisions of, this Agreement do not violate any of the terms, conditions or
provisions of (i) their respective Limited Partnership Agreements, (ii) any
judgment, order, injunction, decree, regulation or ruling of any court or other
governmental authority to which they, or either of them, is subject, or (iii)
except for the documents evidencing and securing the Existing TIAA Mortgage
Loans, any agreement, contract, note, mortgage or indenture to which either of
them is a party or to which any of the property owned by either of them is
subject.

     Section 3.4  Approvals.  No authorization, consent, order, approval or
license from, filing with, or other act by any Governmental Authority or other
Person is or will be necessary to permit the valid execution and delivery by
HMCE and HB of this Agreement or the performance by either of them of the
obligations to be performed by them under this Agreement, which has not been
obtained.

     Section 3.5  United States Person.  Each of HMCE and HB is a "United States
person" within the meaning of Sections 1445(f)(3) and 7701(a)(30) of the
Internal Revenue Code of 1986, as amended.

     Section 3.6  Brokers.  Except for The Carey Winston Company in connection
with the 9300 New ICF Space Lease and the 9302 New ICF Space Lease (the fees of
which shall be paid by the tenant thereunder, Preminger & Glazer in connection
with the Nomura Loan and Carr American and The Evans Company as set forth in
Section 2.6 hereof), no agent, broker, or other Person acting pursuant to
express or implied authority of HMCE or HB is entitled to a commission or
finder's fee in connection with the transactions contemplated by this Agreement
or will be entitled to make any claim against IFA for a commission or finder's
fee.  HMCE and HB have not dealt with any agent or broker in connection with the
transactions contemplated by this Agreement other than as set forth above.

     Section 3.7  Investment Representation. HMCE represents and warrants that
the membership interest in Hunters Branch LLC to be received by it will be
acquired by it solely for its own account and with no intention of distributing
or reselling the membership interest in any transaction which would be in
violation of, or would cause the transactions contemplated herein to violate,
the securities laws of the United States of America, any state thereof or the
District of Columbia, without prejudice, however, to HMCE's right at all times
to sell or otherwise dispose of all or any part of the membership interest in
Hunters Branch LLC (subject to the limitations and qualifications set forth in
the LLC Agreement) under an exemption from registration available under the
Securities Act of 1933, as amended (the "Securities Act"), and any applicable
state or District of Columbia securities law, and subject, nevertheless, to the
disposition of HMCE's property being at all times within its control in
compliance with applicable state and federal regulations.

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     Section 3.8    Pending Litigation.  To the best knowledge of HMCE and HB,
there are no pending actions, suits, arbitrations, claims or proceedings, at
law, in equity or otherwise, affecting all or any portion of the Real Property
or in which HMCE or HB is a party, including judicial, municipal or
administrative proceedings in eminent domain, collection actions, building code
violations, health and safety violations, federal, state or local agency actions
regarding environmental matters, federal environmental protection agency, or
zoning violations, employment discrimination or unfair labor practices, or
worker's compensation, personal injuries or property damages alleged to have
occurred at the Real Property or by reason of the condition or use of or
construction on the Real Property.

     Section 3.9    Default under Permitted Exceptions.  Neither HMCE or HB has
received written notice that it is in default under any document, instrument or
agreement constituting a Permitted Exception, under the Space Leases, or under
any governmental requirements applicable to the Real Property.

     Section 3.10   Leasing Commissions. No leasing commissions are currently
due or shall in the future become due for any current or extension terms of the
Space Leases in effect on October 1, 1997 (except as disclosed in Section 3.6)
and neither HMCE nor HB has any obligation to make tenant improvements for the
Space Tenants under any of such Space Leases.

     Section 3.11   Compliance with Law. To the actual knowledge of HMCE and HB
(without independent investigation or inquiry), all applicable laws, ordinances,
rules, requirements, regulations and building codes of any Governmental
Authorities applicable to the Real Property have been complied with in all
material respects.

     Section 3.12   Documents True. HMCE and HB have delivered to IFA a true,
correct and complete copy of each Contract described on Schedule 1 and each
Space Lease described on Schedule 2.

     Section 3.13   No Options. There do not exist any rights of first offer or
refusals or options to purchase the Real Property or any portion thereof.

     Section 3.14   Space Leases. The Space Leases constitute the entire
agreement between the parties thereto, have not been amended, modified or
supplemented, except for such amendments, modifications and supplements
described on Schedule 2, and there are no leases, tenancy or occupancy
agreements affecting the Real Property other than those described on Schedule 2.
All Space Leases are in full force and effect and there is no default existing
thereunder on the part of HMCE or HB as landlord, or on the part of any Space
Tenants. All services required to be supplied by the landlord under the Space
Leases and all tenant improvements required to be constructed by the landlord
under the Space Leases have been supplied and/or constructed, and neither HMCE
nor HB has received notice of its failure to supply or construct same. The Space
Lease Schedule is true, correct and complete in all material respects.
Notwithstanding the foregoing representation, for any Space Lease for which
Hunters Branch LLC receives a Space Tenant Estoppel Certificate confirming all
of the foregoing, Hunters Branch LLC shall rely on such Space Tenant Estoppel
Certificate in lieu of the foregoing representation, and the foregoing
representation, as to any Space Leases for which a Space Tenant Estoppel
Certificate is received shall not survive closing.

     Section 3.15   Insurance Notices. Neither HMCE or HB has received any
written notice from any of its insurance carriers or any insurance carrier of
any Space Tenant of any defects or inadequacies in the Real Property, or any
portion thereof, which would adversely affect the insurability of the Real
Property or the cost of any such insurance. There are no pending insurance
claims instituted by HMCE or HB with respect to all or any portion of the Real
Property.

             3.16   Structural Defects.  To the best knowledge of HMCE and HB,
without independent investigation or inquiry, there are no material physical or
mechanical deficiencies in the Property except as disclosed on Schedule 3
attached hereto.

             3.17   Environmental. To the best knowledge of HMCE and HB, without
independent investigation or inquiry, other than such substances in such amounts
as are customarily incident to a general office

                                      -8-
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use, and then in such quantities and in such amounts as are not in violation of
any applicable federal, state or local statute or regulation applicable to
Hazardous Substances (as hereinafter defined), (i) no Hazardous Substances or
toxic substances have been treated, stored, handled or disposed of on, under or
at the Real Property; (ii) the Real Property has not been used for industrial
purposes or for the storage, treatment or disposal of hazardous waste or
materials; and (iii) the Real Property has never been listed by a governmental
agency as containing any oil, hazardous waste, hazardous material, chemical
waste or other toxic substance. Further, to the best knowledge of HMCE and HB,
without independent investigation or inquiry, there are no underground storage
tanks under, nor any asbestos or asbestos-containing materials which are
incorporated within any improvements upon, or otherwise located in, on, or under
the Real Property. HMCE and HB have provided to IFA full and complete disclosure
of all studies and information in their possession (or which are readily
available to them) regarding the environmental condition of the Real Property,
and the presence of any Hazardous Substances. Neither HMCE nor HB have
deposited, placed, stored or permitted to be deposited, placed or stored on,
under or in the Real Property, any Hazardous Substances. "Hazardous Substances",
as used herein, means any toxic or hazardous waste, pollutants or substances,
including, without limitation, petroleum products or by-products, asbestos
(irrespective of whether or not encapsulated) and substances defined or listed
as hazardous substances or toxic substances or similarly identified in or
pursuant to the Comprehensive Environmental Response, Compensation and Liability
Act of 1980, as amended, 41 U.S.C. Section 9601, et seq., hazardous materials
identified in or pursuant to the Hazardous Materials Transportation Act, 49
U.S.C. Section 1802, et seq., hazardous waste identified in or pursuant to the
Resource Conservation and Recovery Act of 1976, as amended, 15 U.S.C. Section
2601, et seq. or any hazardous or toxic substance or pollutant regulated under
any other applicable federal or local environmental law;

     Section 3.18   Complete Contribution. The assets being contributed by HMCE
under this Agreement constitute all assets historically required for the
operation of the Real Property.

     Section 3.19   Service Contracts. Except for the Contracts described on
Schedule 1, the Space Leases described on Schedule 2, and the Permitted
Exceptions, there are no service, maintenance, operating or other agreements
affecting all or any part of the Real Property that will be binding on Hunters
Branch L.L.C. after the Closing.

     Section 3.20   Oral Agreements. There do not exist any unwritten agreements
with any Governmental Authority, vendor, Space Tenant, Ground Lessor or
adjoining property owner which is or could become binding on Hunters Branch LLC
or the Real Property after the Closing.

     Section 3.21   Survival. All representations and warranties contained in
this Article shall survive the Closing, except that the representations and
warranties in Section 3.8 through Section 3.20, inclusive, shall terminate
twelve (12) months after the Closing Date unless, within the 12-month period,
HMCE receives notice of a breach of any such representation or warranty.

     Section 3.22   Knowledge. For purposes of this Article III, the knowledge
of HMCE and HB shall be limited to the actual knowledge of David A. Evans and P.
Diane Tipton and shall not include knowledge imputed to HMCE and HB from any
other Person; which HMCE represents are those persons who are the
representatives of HMCE with the most substantive knowledge of the Real
Property, having performed reasonable and diligent inquiry as would be customary
for similar transactions as that contemplated hereby (except as otherwise
indicated in Section 3.11, Section 3.16 and Section 3.17), which inquiry
includes, but is not necessarily limited to inquiry of the existing property
manager.

                                  ARTICLE IV

                     Representations and Warranties of IFA

     IFA makes the representations and warranties in this Article to HMCE and HB
for the purpose of inducing them to execute and deliver this Agreement and to
consummate the transactions contemplated by this Agreement:

                                      -9-
<PAGE>

     Section 4.1  Organization.  IFA is a limited liability company duly
organized, validly existing and in good standing under the laws of the State of
Delaware and is duly qualified as a foreign limited liability company in good
standing in the Commonwealth of Virginia.

     Section 4.2  Authorization.  The requisite number of the members of IFA
required by its limited liability company agreement pursuant to which it is
organized has authorized the execution and delivery of this Agreement and the
transactions contemplated hereby, and the individuals who are executing and
delivering this Agreement on behalf of IFA have been fully authorized and
empowered to do so.

     Section 4.3  No Conflicting Agreements.  The execution and delivery by IFA
of, and the performance and compliance by it with the terms and provisions of,
this Agreement do not violate any of the terms, conditions or provisions of (i)
IFA's limited liability company agreement, (ii) any judgment, order, injunction,
decree, regulation or ruling of any court or other governmental authority to
which it is subject, or (iii)  any agreement, contract, note, mortgage or
indenture to which it is a party or to which any of the property owned by it is
subject.

     Section 4.4  Approvals.  No authorization, consent, order, approval or
license from, filing with, or other act by any Governmental Authority or other
Person is or will be necessary to permit the valid execution and delivery by IFA
of this Agreement or the performance by it of the obligations to be performed by
it under this Agreement, which has not been obtained.

     Section 4.5  United States Person.  IFA is a "United States person" within
the meaning of Sections 1445(f)(3) and 7701(a)(30) of the Internal Revenue Code
of 1986, as amended.

     Section 4.6  Brokers.  Except for The Carey Winston Company in connection
with the 9300 New Space Lease and the 9302 New Space Lease (the fees of which
shall be paid by the tenant thereunder, Preminger & Glazer in connection with
the Nomura Loan and Carr America and The Evans Company as set forth in Section
2.6 hereof), no agent, broker, or other Person acting pursuant to express or
implied authority of ICF Kaiser, ICF Leasing or IFA is entitled to a commission
or finder's fee in connection with the transactions contemplated by this
Agreement or will be entitled to make any claim against HMCE or HB for a
commission or finder's fee.  ICF Kaiser, ICF Leasing and IFA have not dealt with
any agent or broker in connection with the transactions contemplated by this
Agreement other than as set forth above.

     Section 4.7  Investment Representation.  IFA represents and warrants that
the membership interest in Hunters Branch LLC to be received by it will be
acquired by it solely for its own account and with no intention of distributing
or reselling the membership interest in any transaction which would be in
violation of, or would cause the transactions contemplated herein to violate,
the securities laws of the United States of America, any state thereof or the
District of Columbia, without prejudice, however, to IFA's right at all times to
sell or otherwise dispose of all or any part of the membership interest in
Hunters Branch LLC (subject to the limitations and qualifications set forth in
the Limited Liability Company Agreement) under an exemption from registration
available under the Securities Act, and any applicable state or District of
Columbia securities law, and subject, nevertheless, to the disposition of IFA's
property being at all times within its control in compliance with applicable
state and federal regulations.

                                   ARTICLE V

                     Additional Obligations of HMCE and HB

     Section 5.1  Operating Records.  On the Closing Date, HMCE shall deliver to
Hunters Branch LLC all books, records, operating reports, files and other
materials in its possession and control necessary to a complete continuity in
the operation of the Buildings, or copies thereof.

     Section 5.2  Affirmative Covenants.  Between the Effective Date and the
Closing Date, HMCE and HB agree that they will:

                                      -10-
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          (a)  manage and operate the Buildings in the ordinary and usual manner
and maintain in full force and effect until the Closing Date their present
insurance policies described in the Insurance Schedule, or renewals thereof;

          (b)  at their expense, maintain the Buildings in their present order
and condition, make all necessary repairs and replacements and deliver the
Buildings on the Closing Date in substantially the same condition they are in on
the Effective Date, reasonable wear and tear and damage by casualty excepted;

          (c)  perform, observe and comply with all material terms and
provisions of all Space Leases to be performed, observed or complied with by
them as the landlord under such Space Leases;

          (d)  perform, observe and comply with all material terms and
provisions of the Ground Leases to be performed, observed or complied with by
them as the tenants under the Ground Leases; and

          (e)  timely make all payments of principal of and interest on the
Existing TIAA Mortgage Loans (except that HMCE will pay interest only on the
Existing TIAA Loan for the 9300 Building for the month of October), and
otherwise perform, observe and comply with all of the material terms and
provisions of the documents evidencing and securing the Existing TIAA Mortgage
Loans.

     Section 5.3  Negative Covenants.  Between the Effective Date and the
Closing Date, HMCE and HB agree that, without IFA's written consent in each
case, they will not:

          (a)  voluntarily grant, create, assume or permit to exist any
Mortgage, lien, lease, encumbrance, easement, covenant, condition, right-of-way
or restriction upon the Leasehold Estates or voluntarily take or permit any
action adversely affecting the title to the Leasehold Estates as such title
exists on the Effective Date;

          (b)  alter, amend, renew or extend any Space Lease;

          (c)  terminate any Space Lease, or accept a surrender of the leased
premises thereunder, except for nonpayment of rent or a material nonmonetary
default by the Tenant;

          (d)  remove any material item of Personal Property from the Buildings
unless the same is replaced with similar items of equal or better quality before
the Closing Date;

          (e)  defer or otherwise fail to make any repair, replacement or
improvement (excluding, however, capital improvements of a non-emergency nature)
which would or should be undertaken by a prudent owner of property similar to
the Real Property in the Washington, D.C. metropolitan area;

          (f)  allow the status of title to the Real Property to differ from
that which exists as of the Effective Date;

          (g)  incur or allow to exist any indebtedness, obligation or liability
other than as set forth in this Agreement

          (h)  liquidate any Security Deposit, except that a Security Deposit
may be applied to cure a monetary default under a Space Lease which is a failure
to pay rent for a period in excess of sixty (60) days; or

          (i)  commit or allow any waste to the Real Property.

IFA agrees that it will not unreasonably withhold, delay or condition its
consent with respect to any of the matters referred to in this Section 5.3(b) or
5.3(d).

                                      -11-
<PAGE>

     Section 5.4  Expenses.  HMCE and HB agree to pay all expenses incurred by
them in connection with the negotiation, execution and performance of this
Agreement and the transactions contemplated hereby, including the fees and
expenses of its legal counsel.

     Section 5.5  Further Assurances.  HMCE agrees that it will, at any time and
from time to time after the Closing Date, upon request of Hunters Branch LLC do,
execute, acknowledge and deliver, or will cause to be done, executed,
acknowledged and delivered, at no material cost, expense or liability to HMCE,
all such further acts, deeds, assignments, transfers, conveyances and assurances
as may reasonably be required to carry out the terms of this Agreement.

     Section 5.6  New Lease Obligations.    All obligations for tenant
improvements and leasing commissions for Space Leases in effect on October 1,
1997 shall be the responsibility of HMCE and/or HB, as applicable. Neither HMCE
nor HB shall enter into any new leases or enter into any amendments,
modifications, or renewals of Space Leases or otherwise make any changes to any
of the Space Leases without the prior written consent of IFA, which IFA may
withhold in its reasonable discretion.  In the event, subsequent to the date
hereof, HMCE or HB desires to enter into any new leases, HMCE or HB, as
applicable, shall provide IFA with a photocopy of each such lease for approval.
If IFA approves such new lease in writing, HMCE or HB may enter into the new
lease and such new leases shall be considered a part of the Space Leases
hereunder, and IFA shall (i) reimburse HMCE or HB for all tenant improvement and
brokerage commission costs provided for in the lease and incurred by HMCE or HB
in connection therewith, or (ii) on the Closing Date shall assume the obligation
to pay for all commissions, allowances and all other obligations to become due
under or in connection with such new lease(s) by the landlord.

                                  ARTICLE VI

                         Additional Obligations of IFA

     Section 6.1  Expenses.  IFA agrees to pay all expenses incurred by it in
connection with the negotiation, execution and performance of this Agreement and
the transactions contemplated hereby, including the fees and expenses of its
legal counsel.

                                  ARTICLE VII

                  Conditions Precedent to HMCE's Obligations

     The obligations of HMCE to transfer and convey the Property to Hunters
Branch LLC and to perform the other covenants and obligations to be performed by
it on the Closing Date shall be subject to the following conditions (all or any
of which may be waived, in whole or in part, by HMCE):

     Section 7.1  IFA's Representations and Warranties True.  The
representations and warranties made by IFA in Article IV shall be true and
correct on the Effective Date and shall be true and correct in all material
respects on and as of the Closing Date with the same force and effect as though
such representations and warranties had been made on and as of such date; and
IFA shall have executed and delivered to HMCE a certificate, dated as of the
Closing Date, to the foregoing effect.

     Section 7.2  IFA's Performance.  IFA shall have performed all obligations
required by this Agreement to be performed by it on or before the Closing Date.

     Section 7.3  Closing of Nomura Loan.  On the Closing Date, Nomura shall
consummate the closing of the Nomura Loan in accordance with the Nomura
Commitment, unless the failure of such closing to occur is caused by a default
by HMCE or HB in performing any of the obligations to be performed by them under
this Agreement.

                                  ARTICLE VIII

                   Conditions Precedent to IFA's Obligations


                                      -12-
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     The obligations of IFA to perform the covenants and obligations to be
performed by it on the Closing Date, including the obligation of IFA to make the
capital contribution described in Section 2.4 of this Agreement to Hunters
Branch LLC, shall be subject to the following conditions (all or any of which
may be waived, in whole or in part, by IFA):

     Section 8.1    HMCE's and HB's Representations and Warranties True.  The
representations and warranties made by HMCE and HB in Article III shall be true
and correct on the Effective Date and shall be true and correct in all material
respects on and as of the Closing Date with the same force and effect as if such
representations had been made on and as of such date; and HMCE shall have
executed and delivered to IFA a certificate, dated as of the Closing Date, to
the foregoing effect.

     Section 8.2    HMCE's Performance.  HMCE shall have performed all covenants
and obligations required by this Agreement to be performed by it on or before
the Closing Date.

     Section 8.3    Title to Leasehold Estates.  On the Closing Date, HMCE shall
be the sole owner of the Leasehold Estates and such title shall be marketable,
good of record and in fact, and free and clear of all Mortgages, liens,
encumbrances, easements, Leases, conditions and other matters affecting title
other than the Permitted Exceptions.

     Section 8.4    Closing of Nomura Loan.  On the Closing Date, Nomura shall
consummate the closing of the Nomura Loan in accordance with the Nomura
Commitment, unless the failure of such closing to occur is caused by a default
by ICF Kaiser or IFA in performing any of the obligations to be performed by it
under this Agreement.

     Section 8.5    Condemnation.  On the Closing Date, no part of the Land or
the Buildings shall be about to be acquired, or shall previously have been
acquired, by authority of any governmental agency in the exercise of its power
of eminent domain or by private purchase in lieu thereof, nor on the Closing
Date shall there be any threat or imminence of any such acquisition or purchase.

     Section 8.6    Estoppel Certificates.  IFA and Nomura shall have received
(i) estoppel certificates ("Space Tenant Estoppel Certificates") duly executed
by each of the Space Tenants. The Space Tenant Estoppel Certificates shall be
dated not more than thirty (30) days prior to the Closing Date. The Space Tenant
Estoppel Certificates shall be in the form of, and upon the terms contained in,
Exhibit K attached hereto, unless any estoppel form is attached to a Space
Lease, in which event the form required by such Space Lease shall be used, and
(ii) estoppel certificates (the "Ground Lease Estoppel Certificates") executed
by the Ground Lessor substantially in the form attached as Exhibit L. HMCE shall
deliver the Tenant Estoppel Certificates and Ground Lease Estoppel Certificates
to IFA as soon as reasonably possible after receipt thereof.

     Section 8.7    Material Adverse Change.  Between the Effective Date and the
Closing Date, there shall have been no material adverse change in the condition
of the Real Property.

                                  ARTICLE IX

                                    Closing

     Section 9.1    Closing Date.  The closing of the transactions contemplated
by this Agreement (the "Closing") shall take place on October 31, 1997,
simultaneously with the closing of the Nomura Loan. The Closing shall be held at
the office of an attorney-at-law, a title insurance company or a title insurance
agent in the Washington, D.C. metropolitan area mutually acceptable to HMCE and
IFA. Notwithstanding the foregoing, the Closing Date may be postponed by IFA by
written notice to HMCE, to a date not later than November 21, 1997. The date on
which closing is actually consummated is herein referred to as the "Closing
Date".

     Section 9.2    HMCE's Deliveries to IFA.  Subject to the terms and
conditions of this Agreement, HMCE shall deliver, or cause to be delivered, to
IFA on the Closing Date, the following:

                                      -13-
<PAGE>

          (a)  the LLC Agreement, signed by HMCE;

          (b)  the Option Agreement, signed by the Ground Lessors and by HMCE in
its capacity as a member of Hunters Branch LLC;

          (c)  all documents or instruments required to be delivered by HMCE or
the Ground Lessor pursuant to or consistent with the Nomura Commitment,
including a subordination of the Ground Lessor's interest in the Ground Leases
to the deed(s) of trust to be recorded to secure the Nomura Loan, and
Subordination, Non-Disturbance and Attornment Agreements received by HMCE from
each of the Space Tenants, subordinating the Space Leases to the Mortgage
securing the Nomura Loan;

          (d)  evidence of HMCE's authority to consummate the transactions
contemplated by this Agreement;

          (e)  the Space Tenant Estoppel Certificates and Ground Lease Estoppel
Certificates received by HMCE from the Space Tenants and the Ground Lessor;

          (f)  all other documents, instruments, agreements and certificates
required by this Agreement to be signed and/or delivered by HMCE to IFA at the
Closing; and

          (g)  a legal opinion from counsel to HMCE confirming the existence of
HMCE and its authority to consummate the transactions contemplated hereby.

     Section 9.3    IFA's Deliveries to HMCE.  Subject to the terms and
conditions of this Agreement, IFA shall deliver, or cause to be delivered, to
HMCE, on the Closing Date, the following:

          (a)  the LLC Agreement, signed by IFA;

          (b)  the Option Agreement, signed by IFA;

          (c)  evidence of IFA's authority to consummate the transactions
contemplated by this Agreement; and

          (d)  all other documents, instruments, agreements and certificates
required by this Agreement to be signed and/or delivered by IFA to HMCE at the
Closing.

     Section 9.4    IFA's Additional Deliveries to Hunters Branch LLC.  Subject
to the terms and conditions of this Agreement, IFA shall cause to be delivered,
to Hunters Branch LLC on the Closing Date, the following:

          (a)  evidence of ICF Leasing's authority in respect of those
undertakings hereunder contemplated to be performed by it.

          (b)  evidence of ICF Kaiser's authority in respect of those
undertakings to be performed by it pursuant to the ICF Kaiser Lease Guaranty.

          (c)  all documents and instruments required by Nomura to be signed by
ICF Kaiser or ICF Leasing in order to consummate the Nomura Loan, but neither
ICF Kaiser nor ICF Leasing shall be obligated to sign or deliver any document or
instrument that imposes on it any personal liability for payment of the Nomura
Loan; and

          (d)  all other documents, instruments, agreements and certificates
required by this Agreement to be signed and/or delivered by ICF Kaiser to
Hunters Branch LLC at the Closing.

     Section 9.5    Hunters Branch LLC's Deliveries.  Subject to the terms and
conditions of this Agreement, IFA as Managing Member of Hunters Branch LLC,
shall deliver, or cause to be delivered, to ICF Kaiser and/or ICF Leasing, as
applicable, on the Closing Date, the following:

                                      -14-
<PAGE>

          (a)  evidence of Hunters Branch LLC's authority to consummate the
transactions contemplated by this Agreement; and

          (b)  all other documents, instruments, agreements and certificates
required by this Agreement to be signed and/or delivered by Hunters Branch LLC
to ICF Kaiser or ICF Leasing at the Closing.

     Section 9.6    HMCE's Deliveries to Hunters Branch LLC.  Subject to the
terms and conditions of this Agreement, HMCE shall deliver, or cause to be
delivered, to Hunters Branch LLC on the Closing Date, the following:

          (a)  the Ground Lease Assignment for the 9300 Ground Lease and the
Ground Lease Assignment for the 9302 Ground Lease, both signed by HMCE.

          (b)  the Bill of Sale, signed by HMCE;

          (c)  the Space Lease and Contract Assignment, signed by HMCE;

          (d)  instruments terminating the 9300 ICF Space Lease and the 9302 ICF
Space Lease, signed by ICF Kaiser and HMCE;

          (e)  the 9300 New ICF Space Lease, signed by ICF Leasing and HMCE;

          (f)  the 9302 New ICF Space Lease, signed by ICF Leasing and HMCE;

          (g)  the ICF Kaiser Lease Guaranty;

          (h)  the General Assignment, signed by HMCE;

          (i)  all original insurance policies with respect to which premiums
are to be apportioned as of the Closing Date or, if unobtainable, true copies or
certificates thereof;

          (j)  a certification as to HMCE's non-foreign status which complies
with the provisions of Section 1445(b)(2) of the Code, any temporary or final
regulations promulgated thereunder, and any revenue procedures or other
officially published announcements of the Internal Revenue Service or the U.S.
Department of the Treasury in connection therewith;

          (k)  an Affidavit signed by HMCE, addressed to the title insurance
company(ies) designated by Nomura, with respect to the absence of claims which
would give rise to mechanics' liens, the absence of parties in possession of the
Buildings other than Space Tenants under the Space Leases (and other than
subtenants of Space Tenants) and the absence of unrecorded easements granted by
HMCE or HB, in the form customarily required by title insurance companies
insuring title to real property in Fairfax County, Virginia, to eliminate the
exceptions for those matters from Hunters Branch LLC's  and Nomura's title
insurance policy(ies) for the Ground Leases;

          (l)  the Closing Statement referred to in Section 10.1;

          (m)  an original executed counterpart of each Space Lease and Contract
then in effect;

          (n)  all keys to the Buildings and the Personal Property, if any,
which are in HMCE's possession or control, or otherwise obtainable by HMCE
without undue burden or expense, with labels identifying each lock to which such
keys relate;

          (o)  all certificate(s) of occupancy, if any, for the Buildings in
HMCE's possession or otherwise obtainable by HMCE without undue burden or
expense;

                                      -15-
<PAGE>

          (p)  letters signed by HMCE addressed to all Space Tenants in a form
approved by IFA (such approval not to be unreasonably withheld, delayed or
conditioned) notifying such Space Tenants of the transfer of ownership of the
Leasehold Estates and directing the Space Tenants to pay rent that becomes
payable after the Closing Date or rent that is unpaid on the Closing Date, or
both, to Hunters Branch LLC or at its direction;

          (q)  a rent roll, in substantially the same form required by Nomura to
be delivered to Nomura in connection with the Nomura Loan, setting forth all
past due and uncollected Rent owed by Space Tenants, all prepayments of Rent and
all Security Deposits, if any, held by HMCE, its managing agent or any other
Person under all Space Leases;

          (r)  state and local returns, if any, required to report the
transactions contemplated by this Agreement;

          (s)  all documents and instruments required by Nomura to be signed by
HMCE in order to consummate the Nomura Loan, but HMCE shall not be obligated to
sign or deliver any document or instrument that imposes personal liability on it
or its partners for payment of the Nomura Loan; and

          (t)  all other documents, instruments, agreements and certificates
required by this Agreement to be signed and/or delivered by HMCE to Hunters
Branch LLC at the Closing.

     Section 9.7    Hunters Branch LLC's Deliveries to HMCE.  Subject to the
terms and conditions of this Agreement, IFA, as Managing Member of Hunters
Branch LLC, shall deliver, or cause to be delivered, to HMCE on the Closing
Date, the following:

          (a)  the Ground Lease Assignment for the 9300 Ground Lease and the
Ground Lease Assignment for the 9302 Ground Lease, both signed by IFA as
Managing Member of Hunters Branch LLC;

          (b)  the Space Lease and Contract Assignment, signed by IFA, as
Managing Member of Hunters Branch LLC;

          (c)  the Closing Statement referred to in Section 10.1;

          (d)  evidence of Hunters Branch LLC's authority to consummate the
transactions contemplated by this Agreement;

          (e)  state and local returns, if any, required to report the
transactions contemplated by this Agreement, signed by IFA, as Managing Member
of Hunters Branch LLC; and

          (p)  all other documents, instruments, agreements and certificates
required by this Agreement to be signed and/or delivered by Hunters Branch LLC
to HMCE at the Closing.

                                   ARTICLE X

                      Closing Adjustments and Prorations

     Section 10.1   General.  All rentals, revenues and other income generated
by the Buildings and all Real Estate Taxes and Operating Expenses related to the
Buildings shall be paid or shall be prorated between HMCE and Hunters Branch LLC
in accordance with the provisions of this Article. For purposes of the
prorations and adjustments to be made pursuant to this Article, Hunters Branch
LLC shall be deemed to own the Leasehold Estates and therefore be entitled to
any revenues and be responsible for any expenses for the entire day upon which
the Closing occurs. Any apportionments and prorations which are not expressly
provided for in this Article shall be made in accordance with the customary
practice in Fairfax County, Virginia. HMCE and IFA shall cause their accountants
to prepare a separate schedule of adjustments for the Buildings (the "Closing
Statement") before the Proration Date. Any net adjustment in favor of Hunters
Branch LLC shall be paid by HMCE in cash or cash equivalent at the Closing. Any
net adjustment in favor of HMCE shall be paid by Hunters Branch LLC in cash or

                                      -16-
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cash equivalent at, or within 45 days after, the Closing. A copy of the Closing
Statement agreed upon by HMCE and Hunters Branch LLC shall be executed by HMCE
and IFA at the Closing.

     Section 10.2   Rent.  Rent shall be prorated at the Closing in accordance
with the following provisions:

          (a)  Minimum Rent.  Subject to Section 10.2(c) (relating to Delinquent
Rent), Minimum Rent shall be prorated between HMCE and Hunters Branch LLC as of
the Proration Date on an accrual basis based on the actual number of days in the
month during which the Proration Date occurs.  HMCE shall be entitled to all
Minimum Rent which accrues before the Proration Date and Hunters Branch LLC
shall be entitled to all Minimum Rent which accrues on and after the Proration
Date.

          (b)  Additional Rent.  Subject to Section 10.2(c) (relating to
Delinquent Rent), monthly or other payments made by Tenants in advance based
upon projected or estimated Additional Rent shall be prorated between HMCE and
Hunters Branch LLC as of the Proration Date on an accrual basis based on the
actual number of days in the monthly or other period for which the advance
payment is made in which the Proration Date occurs.  Such proration shall be
made separately for each Space Tenant who is obligated to pay Additional Rent on
the basis of the fiscal year set forth in the Space Tenant's Space Lease for the
determination and payment of Additional Rent.  The actual fiscal year for
determination and payment of Additional Rent in which the Proration Date occurs
is hereinafter referred to as the "Applicable Additional Rent Fiscal Year."
Subject to the proration of advance payments required by the preceding sentence,
HMCE shall initially retain all monthly or other payments of Additional Rent
made by each Space Tenant for its Applicable Additional Rent Fiscal Year before
the Proration Date until the Final Closing Adjustment and Hunters Branch LLC
shall initially retain all such monthly or other payments of Additional Rent
made by each Space Tenant for its Applicable Additional Rent Fiscal year on and
after the Proration Date until the Final Closing Adjustment.  HMCE and Hunters
Branch LLC shall prorate the total Additional Rent due from each Space Tenant
for the Space Tenant's Applicable Additional Rent Fiscal Year as a part of the
Final Closing Adjustment pursuant to Section 10.11(b).

          (c)  Delinquent Rent.  Delinquent Rent shall be prorated between HMCE
and Hunters Branch LLC as of the Proration Date but not until it is actually
collected by Hunters Branch LLC after the Closing.  Hunters Branch LLC shall pay
to HMCE when and as collected, and as soon as practicable following receipt, all
Delinquent Rent collected by Hunters Branch LLC after the Closing which is
attributable to the period before the Proration Date, net of the costs of
collection (including reasonable attorneys' fees and costs).  As a part of the
Final Closing Adjustment, any Delinquent Rent which has not as yet been paid
shall be assigned to HMCE, but after the Closing and continuing through and
after the Final Closing Adjustment, without the express written consent of
Hunters Branch LLC, HMCE shall not take any action against a Space Tenant owing
Delinquent Rent which would affect such Space Tenant's right to occupy the
premises leased under its Space Lease, but HMCE may take any other action it
deems necessary or appropriate (in its own name but not in the name of Hunters
Branch LLC) to sue for and collect the Delinquent Rent.  Delinquent Rent
collected by Hunters Branch LLC after the Closing, net of the costs of
collection (including reasonable attorneys' fees and costs), shall be applied in
the following order of priority:

          (1)  in the case of Delinquent Rent which is less than 31 days overdue
as of the Proration Date, against the Space Tenant's Rent obligations in the
chronological order in which they accrue; and

          (2)  second, in the case of Delinquent Rent which is more than 30 days
overdue as of the Proration Date, against the Space Tenant's Rent obligations in
the inverse chronological order in which they accrue.

          (d)  Other Rent Adjustments.  All Rent payable by each Space Tenant
whose Space Lease was terminated before the Proration Date by the terms thereof
(or whose space lease was terminated by agreement prior to the Effective Date)
shall belong entirely to HMCE.  All Rent payable by each Space Tenant whose
Lease commences on or after the Proration Date shall belong entirely to Hunters
Branch LLC.

     Section 10.3   Taxes and Assessments.

                                      -17-
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          (a)  Proration of Taxes at Closing.  All non-delinquent Real Estate
Taxes assessed against the Land and the Buildings shall be prorated between HMCE
and Hunters Branch LLC on an accrual basis, based upon the actual current tax
bill.  All Real Estate Taxes allocable to the period before the Proration Date
shall be the obligation of HMCE and all Real Estate Taxes allocable to the
period on and after the Proration Date shall be the obligation of Hunters Branch
LLC  Any delinquent Real Estate Taxes assessed against the Land the Buildings
shall be paid (together with any interest and penalties) by HMCE at the Closing
in cash or cash equivalent.

          (b)  Post-Closing Refunds of Taxes.  Any refunds of Real Estate Taxes
made after the Closing shall be held in trust by Hunters Branch LLC (and, if
received by HMCE, shall be delivered immediately to Hunters Branch LLC to be
held in trust in accordance with this Section) and shall first be applied to the
unreimbursed costs incurred in obtaining the refund, then paid to any Space
Tenants who are entitled to the same and the balance, if any, shall be paid to
HMCE (for the period prior to the Closing Date) and to Hunters Branch LLC (for
the period commencing on and after the Closing Date).

     Section 10.4   Operating Expenses.  All Operating Expenses and Ground Lease
Rent shall be prorated between HMCE and Hunters Branch LLC as of the Proration
Date on an accrual basis, based on the actual number of days in the month during
which the Proration Date occurs.  HMCE shall be responsible for all Operating
Expenses and Ground Lease Rent attributable to the period before the Proration
Date and Hunters Branch LLC shall be responsible for all Operating Expenses and
Ground Lease Rent attributable to the period on and after the Proration Date.
To the extent commercially reasonable and practicable, HMCE and Hunters Branch
LLC shall obtain billings and meter readings as of the Business Day preceding
the Proration Date to aid in the proration of charges for gas, electricity and
other utility services which are not the direct responsibility of Space Tenants.
If billings or meter readings as of the Business Day preceding the Proration
Date are obtained, adjustments of any costs, expenses, charges or fees shown
thereon shall be made in accordance with such billings or meter readings.  If
billings or meter readings as of the Business Day preceding the Proration Date
are not available for any utility service, the charges therefor shall be
adjusted at the Closing on the basis of the per diem charges for the most recent
prior period for which bills were issued and shall be further adjusted at the
Final Closing Adjustment on the basis of the actual bills for the current
period.

     Section 10.5   Existing TIAA Mortgage Loans.   HMCE shall be responsible
for all costs incurred by TIAA in connection with the Existing TIAA Mortgage
Loans except as set forth below. As of September 30, 1997, outstanding legal
fees charged by Debevoise and Plimpton (the "TIAA Counsel") in its
representation of TIAA in connection with the Existing TIAA Mortgage Loans were
in the amount of $45,135.45, which amount, as well as any additional legal fees
incurred by TIAA in connection with the Existing TIAA Mortgage Loans through the
Effective Date, shall be borne by Hunters Branch LLC. HMCE shall have no
obligation for any payment on account thereof except in respect of the
$30,000.00 contribution being made pursuant to Section 4.2(a) of the LLC
Agreement.

          (a)  Interest.  Accrued interest shall be paid by HMCE at the Closing
through the Effective Date.

          (b)  Escrows.  HMCE shall be credited with and Hunters Branch LLC
shall be charged with the amount of the escrows for Real Estate Taxes and
insurance, if any, held by or on behalf of TIAA on the Closing Date; provided
that TIAA delivers such amounts to Nomura for the account of Hunters Branch LLC.

     Section 10.6   Security Deposits and Other Space Tenant Credits.  Hunters
Branch LLC shall be credited with and HMCE shall be charged with an amount equal
to the sum of (i) all Security Deposits being (or required to be) held by HMCE
or any other Person under the Space Leases (including interest thereon if
required pursuant to the terms of any Space Leases), and (ii) the amount of any
other credits due to Space Tenants as of the Closing Date (other than credits
for free rent or other lease concessions unless in the form of monetary payments
to be made to any Space Tenant) in accordance with the terms of the Space
Leases.  HMCE shall be entitled to retain all Security Deposits or other such
credits due Space Tenants for which Hunters Branch LLC receives credit and HMCE
is charged pursuant to this Section.

                                      -18-
<PAGE>

     Section 10.7   Utility Deposits.  Hunters Branch LLC shall pay to HMCE at
the Closing the amount of all Utility Deposits, against a good and sufficient
transfer by HMCE to Hunters Branch LLC of all interest of HMCE in the Utility
Deposits, unless the utility company's policy is to refuse to honor such
assignment in which case HMCE shall be entitled to retain its Utility Deposits
and Hunters Branch LLC will post new Utility Deposits.

     Section 10.8   Collection of Delinquent Rent.  Hunters Branch LLC shall
have the right after the Closing to collect Delinquent Rent relating to the
period before the Proration Date, but shall not be obligated to do so. Hunters
Branch LLC shall act in a reasonable and diligent manner to collect Delinquent
Rent for the annual period in which the Proration Date occurs, but Hunters
Branch LLC shall not be required to retain counsel or to institute suit or
commence other legal action in order to collect Delinquent Rent. The legal fees
and related costs and expenses incurred in collecting Delinquent Rent shall be
paid by HMCE, subject to any reimbursement obtained in accordance with the Space
Tenant's Space Lease. Hunters Branch LLC shall not waive any Delinquent Rent or
modify or amend any Space Lease so as to reduce the Delinquent Rent owed by the
Space Tenant for any period for which HMCE is entitled to receive such
Delinquent Rent, without first obtaining HMCE's written consent. This Section
shall not prohibit HMCE from suing or taking other action to collect Delinquent
Rent pursuant to Section 10.2(c), subject to the limitations set forth in
Section 10.2(a).

     Section 10.9   Credit for Free Rent.  At the Closing, HMCE shall give
Hunters Branch LLC credit for an amount, determined on an accrual basis, equal
to the abatement of Minimum Rent for any period on and after the Closing Date to
which Space Tenants are entitled under Space Leases in effect on the Effective
Date.

     Section 10.10  Required Statements and Reports.

          (a)  Exchange of Information.  As soon as reasonably practical after
the Closing Date, HMCE shall deliver to Hunters Branch LLC a statement,
certified to be true and correct by HMCE, setting forth all Operating Expenses
incurred by HMCE during the period beginning on the first day of the calendar
year in which the Proration Date occurs (the "Calendar Year of Proration") and
ending on the day before the Proration Date and all reimbursements (if any)
received during such period by HMCE, as landlord, under the Space Leases for
each Space Tenant's share of Reimbursable Expenses for the Calendar Year of
Proration.  As soon as reasonably practical after December 31 of the Calendar
Year of Proration, Hunters Branch LLC shall deliver to HMCE statements,
certified to be true and correct by Hunters Branch LLC, setting forth all
Operating Expenses incurred by Hunters Branch LLC during the period beginning on
the Proration Date and ending on the last day of the Calendar Year of Proration
and all reimbursements received during such period by Hunters Branch LLC, as
landlord, under the Space Leases for each Space Tenant's share of Reimbursable
Expenses for the Calendar Year of Proration.

          (b)  Hunters Branch LLC's Obligation to Bill Space Tenants.  Hunters
Branch LLC shall bill each Space Tenant, at the time and in the manner required
by the Space Tenant's  Space Lease, for the amount (if any) of Reimbursable
Expenses for the Calendar Year of Proration which the Space Tenant is obligated
to pay to Hunters Branch LLC, as landlord under the Space Tenant's Space Lease,
and shall prepare and deliver to each Space Tenant, at Hunters Branch LLC's
expense, all statements and other supporting information required by the Space
Tenant's Space Lease to substantiate the amount billed.

     Section 10.11  Final Closing Adjustment.  Within 180 days after the Closing
Date, HMCE and Hunters Branch LLC shall make a final adjustment to the
prorations made pursuant to this Article (the "Final Closing Adjustment").  The
Final Closing Adjustment shall be made in the following manner:

          (a)  General.  All adjustments or prorations which could not be
determined at the Closing because of the lack of actual statements, bills or
invoices for the current period, the year-end adjustment of Additional Rent, or
any other reason shall be made as a part of the Final Closing Adjustment.  Any
net adjustment in favor of Hunters Branch LLC shall be paid in cash or cash
equivalent by HMCE to Hunters Branch LLC no later than 20 days after the Final
Closing Adjustment.  Any net adjustment in favor of HMCE shall be paid in cash
or cash equivalent by Hunters Branch LLC to HMCE no later than 20 days after the
Final Closing Adjustment.

          (b)  Additional Rent Adjustment.  HMCE and Hunters Branch LLC shall
prorate the actual amount of Additional Rent paid by each Space Tenant for such
Space Tenant's Applicable Additional Rent Fiscal

                                      -19-
<PAGE>

Year (as distinguished from the interim payments prorated as of the Proration
Date pursuant to Section 10.2(a)) as follows:

          (1)  HMCE shall be entitled to the portion of the actual amount of
Additional Rent paid by the Space Tenant equal to the product obtained by
multiplying such amount by a fraction, the numerator of which is the total
amount of Reimbursable Expenses incurred by HMCE during the portion of the Space
Tenant's Applicable Additional Rent Fiscal Year preceding the Proration Date and
the denominator of which is the total amount of Reimbursable Expenses incurred
by HMCE and Hunters Branch LLC during the Space Tenant's Applicable Additional
Rent Fiscal Year; and

          (2)  Hunters Branch LLC shall be entitled to the balance of the
Additional Rent paid by the Space Tenant.

     If the sum of all interim payments on account of Additional Rent collected
and retained by HMCE from each Space Tenant for the Space Tenant's Applicable
Additional Rent Fiscal Year pursuant to Section 10.2(b) (reduced by a pro-rated
portion of the interim payment on account of Additional Rent paid for the month
or quarter in which the Proration Date occurs for which Hunters Branch LLC is
given credit pursuant to Section 10.2(b)) exceeds the amount of Additional Rent
to which HMCE is entitled with respect to such Space Tenant pursuant to
paragraph (1) above, HMCE shall pay such excess to Hunters Branch LLC  If the
sum of all interim payments on account of Additional Rent collected and retained
by Hunters Branch LLC from each Space Tenant for the Space Tenant's Applicable
Additional Rent Fiscal Year pursuant to Section 10.2(b) (increased by a pro-
rated portion of the interim payment on account of Additional Rent paid for the
month or quarter in which the Proration Date occurs for which Hunters Branch LLC
is given credit pursuant to Section 10.2(b)) exceeds the amount of Additional
Rent to which Hunters Branch LLC is entitled with respect to such Space Tenant
pursuant to paragraph (2) above, Hunters Branch LLC shall pay the excess to
HMCE.  The adjustment of interim payments received and actual Additional Rent
paid shall be made separately for each Space Tenant (as opposed to aggregating
all interim payments received by HMCE or Hunters Branch LLC from all Space
Tenants and offsetting the same against the entire amount of Additional Rent
payable by all Space Tenants).  If the sum of the interim payments on account of
Additional Rent collected by HMCE and the interim payments on account of
Additional Rent collected by Hunters Branch LLC exceeds the Additional Rent
actually owed by the Space Tenant for the Space Tenant's Applicable Additional
Rent Fiscal Year, Hunters Branch LLC shall remit to, or give the Space Tenant
credit for, such excess and HMCE and Hunters Branch LLC shall make any necessary
adjustment between them in accordance with the immediately preceding sentences.
If the Space Tenant's Lease requires the Space Tenant to pay Additional Rent on
the basis of more than one category of Reimbursable Expenses, e.g., one or more
components of Operating Expenses and real estate taxes, the prorations required
by this Section 10.11(b) shall be made separately for each category.

          (c)  No Further Adjustments.  Except for: (i) additional or
supplemental real estate taxes, real estate tax credits or rebates, or other
adjustments to real estate taxes due to back assessments, corrections to
previous tax bills or real estate tax appeals or contests, and (ii) any item of
Additional Rent which may be contested by a Space Tenant, the Final Closing
Adjustment shall be conclusive and binding upon HMCE and Hunters Branch LLC and
HMCE and Hunters Branch LLC hereby waive any right to contest after the Final
Closing Adjustment any prorations, apportionments or adjustments to be made
pursuant to this Section.

                                  ARTICLE XI

                                  Termination

     Section 11.1   Reasons for Termination.  This Agreement may be terminated
upon written notice given to the other party by:

          (a)  ICF Kaiser or IFA at the Closing, if any one of the conditions
set forth in Article VIII is not satisfied on the Closing Date; or

          (b)  HMCE at the Closing, if any of the conditions set forth in
Article VII is not satisfied on the Closing Date; or

                                      -20-
<PAGE>

          (c)  ICF Kaiser, IFA or HMCE at any time after November 30, 1997, if
the Closing does not occur before the date on which a notice of termination is
given by one party to the other party.

     Section 11.2   Effect of Termination.  If any party terminates this
Agreement pursuant to Section 11.1, this Agreement shall become null and void
and no party shall have any further liability or obligation to any other party
under this Agreement, except as otherwise provided in the next sentence.  If IFA
or HMCE terminates this Agreement pursuant to Section 11.1(a) or Section
11.1(b) because of a breach by the other party of any of the representations or
warranties made by the other party in this Agreement or the failure of the other
party to perform any of the covenants or agreements to be performed by it under
this Agreement, the terminating party may sue to recover its damages arising out
of such misrepresentation, breach of warranty or default.

     Section 11.3   Right to Seek Specific Performance.  If HMCE, IFA or ICF
Kaiser defaults in performing any of the covenants or agreements to be performed
by it under this Agreement, the other party shall have the right, instead of
terminating this Agreement pursuant to Section 11.1, to elect to permit this
Agreement to remain in effect and to sue for specific performance.

                                  ARTICLE XII

                           Miscellaneous Provisions

     Section 12.1   Entire Agreement.  This Agreement, together with the
Exhibits hereto and any other agreements entered into by and among the parties
hereto simultaneously with, and dated the same day as, this Agreement, contains
the entire agreement between the parties relating to the transactions
contemplated by this Agreement; all prior negotiations between the parties are
merged by this Agreement; and there are no promises, agreements, conditions,
undertakings, warranties or representations, oral or written, express or
implied, between them other than as herein set forth. No change or modification
of this Agreement shall be valid unless the same is in writing and signed by the
parties hereto. No waiver of any of the provisions of this Agreement, or any
other agreement referred to herein, shall be valid unless in writing and signed
by the party against whom it is sought to be enforced.

     Section 12.2   Survival of Agreements.  All provisions of this Agreement
which, by their terms, are to be performed after the Closing Date, shall survive
the Closing.

     Section 12.3   Counterparts.  This Agreement may be executed in any number
of counterparts and it shall not be necessary that each party to this Agreement
execute each counterpart.  Each counterpart so executed (or, if all parties do
not sign on the same counterpart, each group of counterparts signed by all
parties) shall be deemed to be an original, but all such counterparts together
shall constitute one and the same instrument.  In making proof of this
Agreement, it shall not be necessary to account for more than one counterpart or
group of counterparts signed by all parties.

     Section 12.4   Benefit and Burden.  Neither HMCE nor HB may assign its
rights under this Agreement without IFA's prior written consent. Neither ICF
Kaiser nor IFA may assign its rights under this Agreement without HMCE's prior
written consent.  Subject to the foregoing, all terms of this Agreement shall be
binding upon, and inure to the benefit of and be enforceable by, the respective
personal representatives, heirs, successors and assigns of the parties hereto.

     Section 12.5   Governing Law.  This Agreement is intended to be performed
in the jurisdiction in which the Buildings are located and shall be construed
and enforced in accordance with the laws of such jurisdiction, without resort to
conflicts of laws principles.

     Section 12.6   Notices.

          (a)  Manner of Giving Notice.  Each notice, request, demand, consent,
approval or other communication (hereafter in this Section referred to
collectively as "notices" and referred to singly as a "notice")

                                      -21-
<PAGE>

which HMCE, HB, IFA or ICF Kaiser is required or permitted to give to any other
party pursuant to this Agreement shall be in writing and shall be deemed to have
been duly and sufficiently given if

          (1)  personally delivered with proof of delivery thereof (any notice
so delivered shall be deemed to have been received at the time so delivered),

          (2)  sent by Federal Express (or other similar overnight courier)
designating early morning delivery (any notice so delivered shall be deemed to
have been received on the next Business Day following receipt by the courier),

          (3)  sent by United States registered or certified mail, return
receipt requested, postage prepaid, at a post office regularly maintained by the
United States Postal Service (any notice so sent shall be deemed to have been
received two days after mailing in the United States), or

          (4)  sent by telecopier or facsimile machine which automatically
generates a transmission report that states the date and time of the
transmission the length of the document transmitted and the telephone number of
the recipient's telecopier or facsimile machine (with a copy thereof sent in
accordance with paragraph (2) above) (any notice so delivered shall be deemed to
have been received (i) on the date of transmission, if so transmitted before
5:30 p.m. (local time of the recipient) on a Business Day, or (ii) on the next
Business Day, if so transmitted on or after 5:30 p.m. (local time of the
recipient) on a Business Day or if transmitted on a day other than a Business
Day), addressed to the parties at their respective addresses designated pursuant
to subsection (b).

          (b)  Addresses for Notices.  All notices shall be addressed to the
parties at the following addresses:

                    (1)  if to HMCE or HB:

                         c/o Ms. P. Diane Tipton
                         The Evans Company
                         8251 Greensboro Drive, Suite 850
                         McLean, Virginia  22102
                         Telecopy Number: (703) 893-0617

                         with a copy to:

                         Joel N. Simon, Esq.
                         Arent Fox Kintner Plotkin & Kahn
                         1050 Connecticut Avenue, N.W.
                         Washington, D.C.  20036-5339
                         Telecopy Number: (202) 857-6395

                    (2)  if to IFA:

                         Mr. Richard L. Perlmutter
                         Argo Investment Company, LC
                         1355 Piccard Drive, Suite 470
                         Rockville MD 20850
                         Telecopy Number: (301) 948-7642

                         with a copy to:

                         Mr. Clayton Foulger
                         Foulger-Pratt Companies
                         1355 Piccard Drive, Suite 400
                         Rockville, MD  20850

                                      -22-
<PAGE>

                         Telecopy Number:  (301) 948-5949

                         with a copy to:

                         J. Richard Saas, Esq.
                         Tenenbaum & Saas, P.C.
                         4330 East-West Highway, Suite 1150
                         Bethesda, Maryland  20814
                         Telecopy Number: (301) 961-5305

                         Mr. Timothy O'Connor
                         ICF Kaiser International, Inc.
                         9300 Lee Highway
                         Fairfax, Virginia 22031-1207
                         Telecopy Number: (703) 934-3528

                         Paul Weeks, Esq.
                         ICF Kaiser International, Inc.
                         9300 Lee Highway
                         Fairfax, Virginia  22031-1207
                         Telecopy Number:  (703) 934-3029

                         James J. Maiwurm, Esq.
                         Crowell & Moring, LLP
                         1001 Pennsylvania Avenue, N.W.
                         Washington, D.C.  20004-2595
                         Telecopy Number: (202) 628-5116

     Any party may, by notice given pursuant to this Section, change the person
or persons and/or address or addresses, or designate an additional person or
persons or an additional address or addresses, for its notices, but notice of a
change of address shall only be effective upon receipt.  HMCE, IFA and ICF
Kaiser agree that they shall not refuse or reject delivery of any notice given
hereunder, that it will acknowledge, in writing, receipt of the same upon
request by the other party and that any notice rejected or refused by it shall
be deemed for all purposes of this Agreement to have been received by the
rejecting party on the date so refused or rejected, as conclusively established
by the records of the U.S. Postal Service or the courier service.

          (c)  Notice Given by Counsel.  All Notices that are required or
permitted to be given under this Agreement may be given by the parties hereto or
by their respective counsel, who are hereby authorized to do so on the parties'
behalf.

     Section 12.7   Press Release.  HMCE and ICF Kaiser agree that before the
Closing Date they will not issue any press release, advertisement or other
public communication with respect to this Agreement or the transactions
contemplated hereby without the prior written consent of the other party hereto,
except to the extent required by law.  If ICF Kaiser is required by law to issue
such a press release or other public communication before the Closing Date, at
least two Business Days before the issuance of the same it shall deliver a copy
of the proposed press release or other public communication to HMCE for its
review and approval, which approval shall not be unreasonably withheld or
delayed.

     Section 12.8   Partial Invalidity.  If any term or provision of this
Agreement or the application thereof to any persons or circumstances shall, to
any extent, be invalid or unenforceable, the remainder of this Agreement or the
application of such term or provision to persons or circumstances other than
those as to which it is held invalid or unenforceable shall not be affected
thereby, and each term and provision of this Agreement shall be valid and
enforceable to the fullest extent permitted by law.

                                      -23-
<PAGE>

     Section 12.9   Attorneys' Fees.  In the event the parties shall become
engaged in any litigation or with each other in connection with or arising out
of this Agreement, the prevailing party shall be reimbursed and indemnified by
the party not prevailing in such litigation for all costs and expenses
reasonably incurred by the prevailing party in enforcing or establishing its
rights hereunder, including court costs and reasonable attorneys' fees and
disbursements.  The prevailing party shall be determined by the court based upon
an assessment of which party's major arguments or positions taken in the
proceedings could fairly be said to have prevailed over the other party's major
arguments or positions on major disputed issues.

     Section 12.10  Waiver of Jury Trial.  Each party to this Agreement waives
trial by jury in any action, proceeding or counterclaim brought by such party
against any other party on any matter arising out of or in any way connected
with this Agreement.

     Section 12.11  Time of the Essence.  Except as otherwise provided in this
Agreement, time shall be of the essence with respect to each and every provision
of this Agreement.

     Section 12.12  Arm's Length Transaction.  Each of the parties hereto
represents and warrants to each of the other parties hereto that this Agreement
represents the result of arm's length third party negotiation by such party,
that each such party enters into this Agreement of its own accord and free will,
and that each such party has been represented in connection with the negotiation
hereof by competent legal and tax counsel of its own choice.  No party hereto is
relying on any other party hereto concerning or in respect of any tax or other
treatment which may be given such party as a result of the transaction
contemplated hereby, each party hereto relying on its own professional advisors
in connection therewith.

          IN WITNESS WHEREOF, the parties have duly executed this Agreement as
of the day and year first above stated.

      WITNESS:                      HMCE ASSOCIATES LIMITED
                                    PARTNERSHIP, R.L.L.P.


   /s/ Joel N. Simm                 By:   /s/ David W. Evans
-----------------------                 --------------------------------------
                                    David W. Evans, Authorized General Partner



                                    HB LIMITED PARTNERSHIP, R.L.L.P.

                                    By:  HMCE Associates Limited
                                         Partnership, R.L.L.P., its General
                                         Partner


   /s/ Joel N. Simm                 By:  /s/ David W. Evans
-----------------------                  -------------------------------------
                                    David W. Evans, Authorized General Partner



                                    IFA NUTLEY PARTNERS, LLC

                                    By:  Hunters Branch Manager, Inc., its
                                         Managing Member


   /s/ Kary Hilliard
------------------------
                                    By:  /s/ Richard L. Perlmutter
                                         -------------------------------------
                                     Name:   Richard L. Perlmutter
                                     Title:  Vice President

                                      -24-
<PAGE>

EXHIBIT A-1
Description of 9300 Land

EXHIBIT A-2
Description of 9302 Land

EXHIBIT B
Certificate of Formation

EXHIBIT C
Form of Limited Liability Company Agreement

EXHIBIT D
Assignment and Assumption of Ground Leases

EXHIBIT E
Bill of Sale

EXHIBIT F
Assignment and Assumption of Certain Leases, Tenancies and Written Contracts

EXHIBIT G
Assignment of Licenses and Warranties and General Assignment

EXHIBIT H
Form of 9300 New ICF Space Lease

EXHIBIT I
Form of 9302 New ICF Space Lease

EXHIBIT J
Form of Option Agreement

EXHIBIT K
Form of Space Tenant Estoppel Certificate

EXHIBIT L
Form of Ground Lessor Estoppel Certificate

EXHIBIT M
Form of Lease Termination Agreement

                                      -25-